"Officers arrived to find the front door nailed shut, but once inside the home they discovered what they described as a 'prison room' with trash everywhere. There were no beds or chairs in the room.

"Police say four men, ages 79, 54, 74 and about 65, were being kept in the room against their will. One victim says he's been there for about 10 years. Three of the men were physically unable to walk and were transported to LBJ Hospital. The fourth victim is in slightly better condition."

"One of them seemed to think he was picked up off the street and brought here," Houston Police Sgt. J.W. McCoy tells KTRK. "In exchange for beer and cigarettes and a place to stay, he had to turn over his Social Security check."

Update At 6:20 p.m. EDT:

Houston Police spokeswoman Jodi Silva tells reporters that investigators also found four women at the home, but could not say yet whether they too were captives. They were still trying to determine the ages and identities of the women.

Silva said the four men were ages 80, 74, 65 and 50 (which is slightly different than earlier reports above). She says three of the four were found in a garage on the premises and were severely malnourished.

Update At 2:40 p.m. EDT:

Murdock tells the AP that the men were homeless and may have been held so that a captor could cash checks the men were receiving, though the motive for holding the men was not yet clear. He says the men were malnourished and "almost invalids."

He tells AP that one man is in custody and three of the captives have been taken to a hospital for treatment.